Permeability tuner operating mechanism



Sept. 14, 1943. P. K. M GAL L 2,329,635

v PERM EABILITY TUNER OPERATING MECHANISM Original Filed Dec. 24, 1937 4Sheets-Sheet l Z INVENTOR. v

PHILIP K.Mc6A1 L.

BY Muir/36w Sept. 14, 1943. I P. K. M GALL PERMEABILITY TUNER OPERATINGMECHANISM 4 Sheets-Sheet 5 Original Filed Dec. 24, 1937 PHILIP Kf I IE GBEL Sept. 14, 1943. P; K. M GA LL PERMEABILITY TUNER OPERATING MECHANISMSheets-Sheet 4 Original Filed Dec. 24, 1957 INVENTOR. PHILIP K. McGALLple and inexpensive to manufacture.

Patented Sept. 14, 1945 PERMEABILITY TUNER OPERATING MECHANISM Philip K.McGall, Orange, N. J., assignor to Johnson Laboratories, Inc., Chicago,lll., a corporation of Illinois Original application December 24, 1937,Serial No. 181,674. Divided and this application May 9, 1941, Serial No.392,657

11 Claims.

My invention relates to an improved construction of permeability tunerfor radio receiving sets and similar purposes, comprising a plurality ofcombined capacitance and inductance units susceptible of being tuned tores onance at different frequencies, by changing the effectiveinductance of the inductance coils of said units. A tuner of the kindreferred to may consist of as many stages as desired, and it has theadvantage of small bulk per stage, adapting the tuner for use inreceivers where the larger bulk of variable condensers would beundersirable, if not prohibitive.

My invention also includes improved operating means for simultaneouslyand similarly vary ing the efiective inductance of the inductance coilsof said .tuner, to the end that the several tuner units or stages may besimultaneously tuned to resonance at any desired frequency ofalternating current impulses, within the range of the tuner. Saidoperating mechanism thus constitutes a gang control for tuning saidunits, and it is characterized by smoothness of action, absence of lostmotion, positive operation, and mi-crometric effect, at the same timebeing sim- Said operating mechanism is also adapted for use for otherpurposes, as will more fully appear below.

This is a divisional application of my copending application, Serial No.181,674, filed December 24, 1937, now 'Patent No. 2,253,304.

My invention will be best understood by reference to the accompanyingdrawings illustrating a preferred embodiment thereof, in which,

Fig. 1 shows my improved tuner in plan view;

Fig. 2 is a side elevation of the construction shown in Fig. 1;

Fig. 3 is a bottom view of the construction shown in Fig. 1;

Fig. 4 is a vertical, sectional view of the parts illustrated in Figs. 1and 3, taken along the line 4-4 in the latter figures;

Fig. 5 shows in a view similar to Fig. 4 and to an enlarged scale, apart of the operating mechanism of the tuner, consisting of the devicesused to hold the operating rod in operative relation to the operatedrods of said operating mechanism, said operated rods being above saidoperating rod instead of below the latter as illustrated in Fig. 4;

Fig. 6 is a vertical, sectional view of the parts shown in Fig. 5, takenalong the line 6-6 in that figure;

Fig. 7 is a horizontal, sectional view to an enlarged scale, of a partof the construction shown in Fig. 1, taken along the line 1-'! in thatFig. 8 shows in a view similar to Fig. 5, a modified construction ofoperating mechanism, in which one operated rod is employed instead oftwo of said rods as shown in Fig. 5;

Fig. 9 is a vertical, sectional view of the parts shown in Fig. 8, takenalong the line 99 in that figure;

Fig. 10 shows in a view similar to Fig. 5, a further modifiedconstruction of operating mechanism, in which two operated rods aremoved simultaneously in opposite directions by the operating rod,instead of in the same direction as illustrated in Fig. 5;

Fig. 11 is a vertical, sectional view of the parts shown in Fig. 10,taken along the line H--H in that figure;

Fig. 12 is a right handend view to an enlarged scale, of one of theoperated rods shown in Fig. 3, and illustrates the manner of connectingsaid rods with the movable plate connected in turn with the cores ofmagnetic material to operate the same;

Figs. 13, 14 and 15 show respectively, modifled means for connectingsaid operated rods with said movable plate;

Fig. 16 is a vertical, sectional view of the parts shown in Fig. 15,taken along the line l6l6 in that figure;

Fig. 17 is a horizontal, sectional view of the construction shown inFig. 1, taken along the line ll-ll, excepting that in this view theshield of the sectioned tuner unit is shown in side elevation, and thecover of the tuner is shown in place;

Fig. 18 illustrates in a view similar to Fig. 17, the combination of twotuners of the construction illustrated in Figs. 1 to 4 inclusive, toillustrate the tuning of two multi-stage tuners, by means of a singleoperating rod;

Fig. 19 illustrates diagrammatically, the adaptation 'of my improvedtuner to a remote control system; 7

Fig. 20 is a horizontal, sectional view of a part of the structure shownin Fig. 4, taken along the line 20-40 in that figure; and

Figs. 21 and 22 illustrate respectively in views similar to Fig. 5,modified forms of operated rods for actuation by the operating rod.

Similar numerals refer to similar throughout the several views.

As shown in Figs. 1 to 4 inclusive, my improved tuner consists of ahousing comprising a bent sheet metal plate l0 forming the front partsand side walls of said housing, and a sheet metal shelf II having frontand side flanges secured respectively to the front and side walls of theplate I0. the front flange of said shell" extending upwardly and itsside flanges extending downwardly. Said shelf II is also provided withadownwardly extending flange at its rear edge. Above the shelf II, thefront wall of the housing has secured to it a plurality of blocks I2 ofinsulating material, each of which blocks supports with a sliding fit,the front end of a tubular support I3 of insulating material on whichthe inductance coil I4 of the corresponding unit of the tuner, is wound.The rear end of each insulating tube I3 is supported with a slidingfit,v

in a small plate I5 of insulating material which is in turn supportedfrom the shelf I I by a metal angle bracket I6. As shown in Fig. 20, thefront end of the tube I3 contains a cross member I! connected at itsends with said tube, which cross member is connected by a stud I8 withthe central portion of a flat spring I9 resting at its ends against thecorresponding block I2. A screw 20 threaded through the front wall ofthe tuner housing, rests at its inner end against the midportion of thespring I9, said spring having a conformation moving the tube I3 to itsextreme forward position when the screw 20 is turned to move itforwardly away from the block I2. The spring I9 and the parts describedas co operating therewith, constitute a means for moving axially thetube I3 and the coil I4 carried thereby, to align said coils relativelyto each other for effective and accurate gang operation of theinductance changing devices respectively associated with said coils, bythe common operating mechanism below described.

Each of the tubes l3 contains a core ll of magnetic material, preferablycornminuted magnetic material compressed into solid form, which core maymove freely axially in the tube I3 to change as desired, the effectivepermeability of the magnetic path through and around the correspondingcoil I l, and correspondingly changes the inclucfance of said coil. Therear end of each core 2! isconnected with a short rod 22, the rear endof which is connected with and supported by a small plate of insulatingmaterial 23, which, as shown in Fig. 7, is rigidly connected with theupper portion of metal bracket 24 extending through a slot 25 thereforin the shelf II, shown in Figs. 1 and 3. As shown in Figs. 3 and 7, thelower portion of each bracket 24 extends through an opening therefor inan operating plate 26, and is rigidly secured below said plate to aflange 26a extending downwardly from the rear edge of said operatingplate.

As shown in Figs. 1, 3 and 4, the shelf II has formed therefrom upwardlyprojecting ribs 21 extending from front to rear of said shelf betweenthe coils I4, forming corresponding grooves in the lower surface of saidshelf. As shown in Fig. 4, each of the ribs 21 engages the lowerportions of adjacent shields 28 provided to enclose the coils I4 andtheir cores 2|, to hold said shields against lateral movement, andcentrally around said coils I4. Each of said shields 28 is provided witha longitudinal slot 28a in its bottom wall, to clear the correspondingbracket 24 and to also clear the connection between the the bracket I8serves as a guide in moving the shield around the coil I4, and holds theshield adjacent the shelf II. Each of the blocks I2 fits in the open endof the corresponding shield 28, as a result of which the shields when inplace, are held at their front ends against lateral movement in anydirection. The rear ends of said shields are held against movement, asbelow described.

The operating plate 26 as shown in Fig. 3, is

shorter from front to rear, than the shelf II, so that its operatingmovement is equal to the tuning movement to be imparted axially to thecores 2I. The plate 26 is provided with upwardly extending ribs'29fitting the grooves in the ribs 27, to guide the plate 26 in itsmovement under the shelf II. As shown'in Figs. 3 and 4, bars 30 and 3Iextend horizontally from the front wall of the tuner housing to the rearflange on the shelf II, to which their ends are rigidly secured, theupper. edges of said bars being spaced slightly from the operating plate26, the flange 26a. of which is provided with apertures through whichsaid bars extend with sliding fits. In the spaces between the bars 30and 3I and the plate 26, flat springs 32 carried by said plate aredisposed which press the plate against the shelf II and hold the ribs 29in sliding engagement with the grooves in the ribs 21. The lower edgesof the bars 30 and 3I are somewhat above the bottom of the housing In,to clear the cover of the latter, as below described. The plate 26 thusconstitutes a means for imparting simultaneous and equal movement to thecores 2|, making gang tuning of the several inductances possible fordifferent frequencies within the range of the tuner.

As indicated diagrammatically in Fig. 4, each ofthe blocks I2 carries aflat capacitor 33 having terminals 34 and 35, for connection with theterminals of the corresponding coil I4, which terminals 34 and 35 arealso the terminals of the corresponding unit of the tuner for connectionas desired, according to the requirements of the circuit or hook-up withwhich the tuner is used, whether superheterodyne, tuned radio frequency, or otherwise. The capacitors 33 are of any kind well known inthe art and preferably provided with sufficient adjustment for aligningpurposes, but are otherwise fixed.

In constructing the tuner, the coils M are wound to have as nearly aspossible, identical electricalcharacteristics, and the cores 2| are madeas closely as possible, duplicates as to dimensions and permeability.The coils and cores are then mounted as described, and by aligning thecoils by the screws 20, the same inductance relation is establishedbetween each coil and its core, as between each. other coil and itscore. Then, preferably with the cores drawn to the limit of theirmovement from Within the coils, each unit of the tuner is tuned toresonance by aligning adjustment of its capacitor 33, and the tuner asto all of its units or stages, is in tune or resonance for the highestfrequency of the range of the tuner. Movement of the cores 2I into thecoils I4 by the operating plate 26, equally increases the permeabilityof the magnetic paths of the several coils for any particular positionof said cores, correspondingly and equally increasing the inductance ofsaid coils and establishing a tuned or resonant condition of all of theunits or stages of the tuner for any desired frequency within the rangeof the tuner, which is lower than the limiting high frequency of saidrange.

The means I employ to operate the plate 26, consists as shown in Figs. 3and 4, of an operating rod 36 having rotary movement, which rod extendsperpendicularly through one of the side walls of the housing l andthrough the bar 3|, a bushing 31 being mounted in said side wall toconstitute a bearing for said rod, which rod is prevented from movingaxially in said bearing by split rings 38 carried by said rod atthe'ends of said bushing. Two operated rods 39 are mounted below the rod36, between and parallel with the bars 30 and 3|, with their rear endsattached to the flange 26a. The rod 36 is provided with grooves 36a inline with the rods 39, in which grooves the rods 39 are held infrictional engagement by rollers 40 below said rods 39, said rollers 40being pressed upwardly against said rods 39 and in turn pressing saidrods upwardly into the grooves 36a, by a spring 4| extending at itsmid-portion over and pressing downwardly against the rod 36, and at itsends extending under and pressing upwardly against the mid-portions ofthe rollers 40. In Figs. 5 and 6, the relation between the rod 36 andthe rods 39 is more clearly shown. In these figures the rods 39 areabove the rod 36 instead of below the latter rod as shown in Fig. 4, butthe relation between said rods operatively, is the same in both cases.As shown in Fig. 5, the grooves 36a are provided with inclined sidesurfaces diverging outwardly, said grooves being deep enough to clearthe surfaces of the rods 39 which are nearest the axis of the rod 36,

so that the rods 39 engage only said side surfaces. Between the grooves36a, the rod 36 is provided with a groove 362) containing the midportionof the spring 4|, and the rollers 40 are provided at their mid-portionswith groove 40a containing the end portions of said spring. The ends ofthe spring 4| are extended sufficiently around the rollers 40, so thatin use, rotation of the rod 36 and the resultant longitudinal movementof the rods 39, will rotate the rollers and cause them to slip at theirpoints of engagement with said spring, without changing the generalrelation of the spring to the rollers 4|]. By engaging the surfaces ofthe rod 36 and of the rollers 40 which are remote from the surfaces ofengagement between the rod 36 and the rods 39, the tendency of thespring 4| to elongate or straighten, presses the rollers 40 towards therod 36, and maintains the frictional engagement between the rod 36 andthe rods 39. This produces a smooth and even longitudinal movement ofthe rods 39 by rotation of the rod 36, without any irregularity ofaction, which makes possible exact and smooth operation of the movableparts of the tuner, even in imperceptible amounts, 2. condition greatlyto be desired in effecting exact tuning. As shown in Figs. 1 and 2, therod 36 has secured to its outer end, an operating knob 42,. and the muchgreater diameter of the knob than the diameter of the surfaces of therod 36 engaging the rods 39, gives the operating mechanism a micrometricaction, which also facilitates exact tuning. It will be noted in Fig. 6,that the radius of curvature of the curved end portions of the spring 4|engaging the rollers 49, is substantially greater than the radius ofcurvature of the'surfaces of said rollers 4|] engaged by said spring. Asa result, when the tuner is substantially in tune for. a desiredfrequency, and exact tuning is required, a small amount ctr-oilingaction of the rollers on the spring 4| occurs without slippage of saidparts on each other, which further facilitates effecting exact tuning,by lessening the drag on the operating rod 36.

With the operating mechanism described, several complete rotations ofthe rod 36 are required to move the plate 26 through its tuning range,and to afford an indication of the frequency for which the tuner isadjusted at any time, the plate '26 is provided with an arm 43 (Figs. 1,2 and 3), extending through a slot 44 in a side wall of the housing |0(Fig. 2), which arm is connected with an indicating pointer 45 adjacenta scale 46 on the housing, calibrated in any desired units. Obviously,any equivalent indicating means operated by the arm 43 may be employedas desired, depending upon the location of the tuner and the partsassociated therewith in any case.

To enclose the operating mechanism, a cover plate 41 (Fig. 17) isemployed. With the unit shields 28 in place as above described, theupper rear flange 41a of.the cover plateis located on top of the rearends of said shields, the rear wall 411: of the said cover plate extendsadjacent the rear end walls of the shields 28, and the bottom wall 410of said cover plate extends horizontally in the bottom plane of thetuner housing ID, a front flange 41d on said cover plate extending.upwardly just inside of the front wall of the plate In of the tunerhousing. The cover plate is of a width equal .to the distance betweenthe side walls of the plate i0,

encloses the tuner, and produces a self-contained 7 structure that ismuch more compact than is possible by the use of conventionalinterleaved variable capacitors, which structure is a com pletemulti-stage tuner that is thoroughly shielded and entirely enclosed, andrequires in addition, only suitable radio tubes, a suitable currentsource, and wiring therefor, connected with the tuner in accordance witha desired hook- Lip or circuit, to make an operative tuning sys- It willbe understood that I do not limit myself in constructing the tunersdescribed, to the particular number of units illustrated, since eachtuner may consist of as many units or stages as desired. In Fig. 18 Iillustrate means that may be employed to operate and tune two completetuners of the kind described, by a single operating rod. Part of afirst-tuner as above described, is shown, having a housing It], a shelfshields 28, an operating plate 26 and an operating rod 36. A secondsimilar tuner is shown, having a housing Illa, a" shelf Ila. shields 28band an operating plate 26b, but no operating rod. The bottom edges ofthe housing H) are held against the bottom edges of the housing Illa, bya cover plate 48 secured to the rear flanges of the shelves II and Na,which cover plate has upper and lower flanges 48a extending over the endportions of the shields 28 and 28b. The front walls of the housings l0and Illa are held together by a connecting plate 49 secured to saidfront walls. The flanges 26a and 260 of the operating plates 26 and 26brespectively, are connected by plates 50 secured to said flanges asindicated. The operating devices connecting the operating rod 36 withthe operating plate 26, are the same as above described. and are omittedin Fig. 18 for the sake oi clearness. As a result of the constructionshown in Fig. 18, rotation of the rod 36 operates the plate 28 with theresults above described, and at the same time operates the operatingplate 26b of the second tuner with similar results as to the secondtuner, and all of the units or stages of both tuners are thussimultaneously operated and tuned by means of a single operating rod.Thus a plurality of tuners, each complete for its intended purpose andconsisting of as many stages as desired, may be simultaneously tuned bya single .operating rod, and said complete tuners may be severally usedfor any purposes desired and either simultaneously or alternately, forexample, as tuning means for different frequency bands.

As illustrated in Fig. 19, my tuner described,

is adapted for use in any case where the tuning units must have onelocation and the operating means or controlling devices must have asecond location which may be remote from said flrst location. In thisfigure my tuner is shown diagrammatically at H], its operating rod 36being connected by a flexible shaft 5| with an operating knob 52 on acontrol board 53 remote from the tuner H]. The arm 43 of the tuner, isconnected with a wire 54 extending through a tube 55 to the controlboard 53, where said wire is connected with a pointer 56 movable by saidwire along a scale 51 carried by said control board. The ends of thetube 55 are supported by brackets 58 and 59 carried respectively by thetuner l0 and the control board 53.

The manner of operating the frequency indicating pointer 56 asdescribed, gives a correct indication at any time of the frequency towhich the units of the tuner are tuned, in the system of units used inlaying out the scale 51, regardless of whether there is slippage in thefriction mechanism above described between the operating rod 36 and thecores 21, since the knob 52 is not relied upon to indicate by itsangular posi- .tion, the frequency for which the tuner is set at anytime. Although there is little probability of slippage between theoperating rod 36 and the operated rods 39 described in connection withFigs. 3 to 6 inclusive, such slippage is possible unless prevented. Ieliminate the possibility of such slippage to an appreciable extent, bysecuring to the inner end of the rod 36, a pinion 50 (Figs. 3 and 4),meshing with a rack 6| disposed parallel with the operated rods 39 whichrack is rigidly secured at one end to the flange 26a. The other end 61aof the rack BI is in sliding engagement with the upper surface of thebar 30, thereby holding the rack in mesh with the pinion 60. The pitchdiameter of the pinion 69 should equal the diameter of the contactcircles in the grooves 36a with the rods 39 to insure against slippagebetween the operating rod 36 and the operated rods 39, due to the actionof said pinion. I

The operated rods 39 may be connected with the flange 26a of theoperating plate 26, in any one of a number of ways, several of which areshown in Figs. 12 to 16 inclusive. In each of these cases, each of therods 39 is provided with a circumferential groove 39a near its end tofacilitate said connection. In Fig. 12 the flange 26a is provided withan edge slot 26d fitting the groove 39a, and after the rod 39 is pressedto the bottom of said slot, an edge tongue 26s of the flange 26aadjacent said slot, is forced over and into the slot 26d and into thegroove 39a, locking the rod 39 in said slot. In Fig. 13 the flange 26fis provided with clearance holes 269 for the rods 39, and after they areinserted in said holes with the adjacent parts of the flange 26) in thegrooves 39a, the rods 39 are held in the position shown in Fig. 13 by aspring 62 bent at its midportion to go over the edge of the flange 26fwith the ends of said spring on opposite sides of said flange andextending under and partly around and pressing upwardly on the rods 39respectively. In Fig. 14, the flange 26h is provided with edge slots 26fitting the grooves 39a in the rods 39, and when said rods are pressedto the bottoms of said slots, they are held in the position shown inFig. 14 by a spring 63 bent at its midportion to go through a hole 291'in the flange, with the ends of said spring extending on opposite sidesof said flange and over and pressing downwardly on said rods 39respectively. As shown in Figs. 15 and 16, the flange 2670 is providedwith a clearance aperture 26m for each of the rods 39, and a U-shapedmetal clip 64 having similar clearance apertures through its legs, isemployed. The clip is placed on the flange with the clip apertures inline' with the flange aperture 26m, the grooved end of a rod 39 isinserted through said apertures with the groove 39a in line with theflange 26k, and a set screw 65 threaded through the mid-portion of theclip 64 and resting against the edge of the flange 26k, is tightened,drawing the clip 64 and the rod 39 downwardly until the groove 39a istightly against the bottom of the aperture 26m, in which position theparts are held by the set screw.

In constructing the operating mechanism above described, I do not limitmyself to the form and detail shown, since said mechanism may be made inmany equivalent ways as far as operation and results are concerned,without departing from my invention in its generic aspect. Essentiallymy improved operating mechanism includes a rotary operating rod, anoperated rod to which movement is imparted axially by angular movementof said operating rod, there being frictional engagement between saidrods resulting preferably from substantially opposed surfaces of orcarried by one of said rods engaging correspondingly opposed sidesurfaces of a groove in or carried by the other of said rods, saidsurfaces being held in frictional engagement with each other by pressureof an amount determined by the degreeof said frictional engagementrequired by the purpose for which said operating mechanism is used. Itwill be understood that said operating mechanism may be used for anypurpose requiring the changing of angular motion into translatory oraxial motion of an operated member or rod, as long as the force sotransferred is within the limits of the frictional engagement referredto.

In Figs. 8 and 9 I show a modified form of operating mechanism in whichbut one pressure roller and one operated rod are used, instead of two ofsaid rollers and two of said rods, a illustrated in Figs. 3, 4, 5 and 6.As shown in Fig. 8, the operating rod 360 is provided with a groove 36dhaving outwardly diverging side walls and engaging an operated rod 391)in said groove, in the same manner that each of the grooves 36a engagesa corresponding rod 39 as above described in connection with Figs. 5 and6. On each side of the groove 36d, the rod 360 is provided with a groove36c containing one end portion of a spring 66,-the other end portion ofwhich is in a groove 61a in a roller 61, which roller is provided with acentral groove 61b receiving the operated rod 39b. The form of thesprings 66 which press the roller 6'! against the'operated rod 391) andso press the operated rod into the groove 36d, is shown in Fig. 9, whichalso shows the position of the roller 61 immediately over the operatingrod 360, this View further illustrating the shape of the end portions ofeach of the springs 66, which permits a small amount of rolling movementof the roller 61 on said springs, in making accurate adjustments of therod 39b. This construction is adapted to move not only rigid operatedrods, but also operated rods that are more or less flexible, whereas theconstruction shown in Figs. and 6 is adapted particularly for use withoperated rods that are rigid and have little flexibility. A furtheradvantage of the construction shown in Figs. 8 and 9, is

that greater pressure of the operated rod against the operating rod mayreadily be obtained, as a result of using two springs per roller and peroperated rod, instead of one spring as shown in Figs. 5 and 6. I

In Figs. 10 and 11 I Show a modification of the operating mechanism lastdescribed, in which two operated rods 3% arein frictional engagementwith the inclined side walls of the groove 36d in the operating rod 360,one of said rods 39b being above and the other being below the operatingrod, and each of said operated rods 3% being held in engagement with theoperating rod 36c by a pair of springs 66 inthe manner described inconnection with Figs. 8 and 9. The two grooves 36c in the operating rod360, receive the end portions of both'sets of springs, the parts beingof the same construction and operating in the same manner as describedin connection with Figs. 8 and 9, and ing that two operated rods 39b areemployed. This construction provides for moving operated mechanisms indifferent directions from each other, by a single angular movement of anoperating rod.

While I have so far illustrated the operated rods as having circularcross-sections, it will be understood that they may be of any form ofcross-section that will effect frictional engagement of the kinddescribed, with an operating rod. For example, in Fig. 21 I illustrate afiat operated rod 68 having frictional engagement at-its edge portions,with the outwardly diverging side walls of a groove 69a in an operatingrod 69, it being understood that the rod 68 may be held in saidfrictional engagement, by. any of the means above described and notshown in Fig. 21, to avoid needless duplication. In Fig. 22 I show amodification of the construction shown in Fig.

which a flat operated rod 10 and an operating rod H are employed, whichhave the same frictional relation to each other as the rods 68 and 69shown in Fig. 21, and in addition, the

groove Ha in the rod II, which frictionally engages the edge portions ofthe rod 10, carries at its mid-portion, outwardly extending gear teeth 1lb meshing with corresponding rack teeth 10a. in the lower surface ofthe rod I0, to prevent relative displacement between the rods I0 and IIdue to slippage at their surfaces of frictional engagement, therebyavoiding the need for additional gear and a separate rack for thatpurtially exerted between each operated rod and the the only differencebe-- operating rod by the springs and rollers described, and in thiscase the lateral pressures developed by the small inclination of theside walls of the groove or grooves in the operating rod, pro'duceforces which are balanced and self-contained in the operating rod, andalso produce balanced lateral forces which are self-contained in theoperated rod or rods, the spring pressure exerted in holding the rodstogether 'being balanced against the operating and operated rods so thatthe said forces are balanced within the operating mechanism consideredas a whole.

With this construction the only force required M to move the operatingmechanism, is that re- .quired to overcome the friction between theoperated rod and the side walls of the groove of the operating rod.

While I have shown my inventionin the particular embodiment abovedescribed, it will be understood that I do not limit myself thereto, asI may employ equivalents thereof known to the art at the time of thefiling of this application, without departing from the scope of theappended claims.

Having thus described my invention, claim is:

1. In an operating mechanism, the combination of a plurality of elementsmounted for simultaneous reciprocating movement, a member connected andmovable with said elements, an operating rod having a groove withoutwardly diverging side walls, an operated rod secured to said memberand extending across said operating rod what I with its opposite sidesurfaces in engagement with said groove side walls, a roller crossingand engaging the side ofsaid operated rod remote from said operatingrod, and spring means engaging and pressing with equal and oppositepressure against relatively remote sides of said roller and saidoperating rod and tending to move said roller and said operating rodtowards each other.

2. In an operating mechanism, the combination of a plurality of elementsmounted for simultaneous reciprocating movement, a member connected andmovable with said elements, an operating rod having a diverging sidewalls, an operated rod secured to said member and extending across saidoperating rod with its opposite side surfaces in engagement with saidgroove side walls, a roller crossing and engaging the side of saidoperated rod remote from said operating rod, and spring meansenoperating rod having a groove with outwardly diverging side walls, anoperated rod secured to said member and extending across said operatingrod with its opposite side surfaces in engagement with said groove sidewalls, a roller crossing and engaging the side of said operated rodremote from said operating rod, and spring means engaging and pressingwith equal and opposite pressures against relatively remote sides ofsaid roller and said operating rod and tending to groove with outwardlyI move said roller and said operating rod towards each other, saidspring means having an end conformation retaining said roller inengagement with said spring means and affording a limited range ofrolling movement of said roller on said spring means.

4. In an operating mechanism, the combination of an operating rod havinga circumferential groove, an operated rod in said groove and extendingacross said operating rod, a roller crossing and engaging the side ofsaid operated rod remote from said operating rod, and spring meansengaging and pressing with equal and opposite pressures againstrelatively remote sides of said roller and said operating rod andtending to move said roller and said operating rod towards each other.

5. In an operating mechanism, the combination of an operating rod havinga circumferential groove, an operated rod in said groove and extendingacross said operating rod, a roller crossing and engaging the side ofsaid operated rod remote from said operating rod, and spring meansengaging and pressing with equal and opposite pressures againstrelatively remote sides of said roller and said operating rod andtending to move said roller and said operating rod towards each other,said spring means having an end conformation retaining said roller inengagement with said spring means.

6. In an operating mechanism, the combination of an operating rod havinga circumferential groove, an operated rod in said groove and extendingacross said operating rod, a roller crossing and engaging the side ofsaid operated rod remote from said operating rod, and spring meansengaging and pressing with equal and opposite pressures againstrelatively remote sides of said roller and said operating rod andtending to move said roller and said operating rod towards each other,said spring means having an end conformation retaining said roller inengagement with said spring means and affording a limited range ofrolling movement of said roller on said spring means.

'7. In an operating mechanism, the combination of an operating rodhaving a circumferential groove, an operated rod in said groove andextending across said operating rod, said groove having outwardlydiverging side walls, and said operated rod having engagement with saidside walls and being otherwise free from engagement with said operatingrod, a roller crossing and engaging the side of said operated rod remotefrom said operating rod, and spring means engaging and pressing withequal and opposite pressures against relatively remote sides of saidroller and said operating rod and tending to move said roller and saidoperating rod towards each other.

8. In an operating mechanism, the combination of an operating rod havinga circumferential groove, an operated rod in said groove and extendingacross said operating rod, said groove having outwardly diverging sidewalls, and said operated rod having engagement with said side walls andbeing otherwise free from engagement with said operating rod, a rollercrossing and engaging the side of said operated rod remote from saidoperating rod, and spring means engaging and pressing with equal andopposite pressures against relatively remote sides of said roller andsaid operating rod and tending to move said roller and said operatingrod towards each other, said spring means having an'end conformationretaining said roller in engagement with said spring means.

9. In an operating mechanism, the combination of an operating rod havinga circumferential groove, an operated rod in said groove and extendingacross said operating rod, said groove having outwardly divering sidewalls, and said operated rod having engagement with said side walls andbeing otherwise free from engagement with said operating rod, a rollercrossing and engaging the side of said operated rod remote from saidoperating rod, and spring means engaging and pressing with equal andopposite pressures against relatively remote sides of said roller andsaid operating rod and tending to move said roller and 'said operatingrod towards each other, said spring means having an end conformationretaining said roller in engagement with said spring means and affordinga limited range of rolling movement of said roller on said spring means.

10. In an operating mechanism, the combination of an operating rodhaving a circumferential groove, operated rods in said groove onopposite sides of and extending across said operating rod, a rollercrossing and engaging the side of each of said operated rods remote fromsaid operating rod, and spring means engaging and pressing with equaland opposite pressures against relatively remote sides of each of saidrollers and said operating rod and holding the corresponding operatedrod in engagement with said operating rod, said groove having outwardlydiverging side walls, and each of said operated rods having engagementwith said side walls and being otherwise free from engagement with saidoperating rod.

11. In an operating mechanism, the combination of an operating rodhaving a circumferential groove, operated rods in said groove onopposite sides of and extending across said operating rod, a rollercrossing and engaging the side of each of said operated rods remote fromsaid operating rod, and spring means engaging and pressing with equaland opposite pressures against relatively remote sides of each of saidrollers and said operating rod and holding the corresponding operatedrod in engagement with said operating rod, said groove having outwardlydiverging side walls, and each of said operated rods having en'-gagement with said side walls and being otherwise free from engagementwith said operating rod, said spring means having end conformationsretaining. said rollers respectively in engagement with said springmeans.

PHILIP K. McGALL.

CERTIFICATE OF CORRECTION. Patent No. 2,529,655. .September lL 19b5,

PHILIP K. TICGALL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 5,first column, line MD, for "groove" read "grooves"; page 5, firstcolumn, line 70, after "for" insert --an; and second column, line 59,claim 1, for

pressure read -pressures; page 6, second column, line 16, claim 9. for

"divering" read "diverging-q and that the said Letters Patent should beread with this correction therein that the same may conform to therecord of the case in the Patent Office.

.Signed and sealed this 9th day of November, A. 1'). 191g.

' v a Henry Van Arsdale, (Seal) Acting Commissioner of Patents.

